Abstract: There is a large number of layered and quasi-layered dolerite in the Dahua area of western Guangxi, and their petrogenesis is of great significance to the understanding of the regional tectonic evolution processes and the characteristics of the mantle source. In this paper, geochemical and Sr-Nd isotopic studies of Dahua dolerite show that the Dahua dolerite belongs to the alkaline basalt series, with high TiO₂ content (2.00~3.82 wt.%) and Ti/Y ratios (860~1176) and generally has the content and characteristics of rare earth element and trace elements similar to those of the high-Ti/Y Emeishan basaltic serie, which may represent the eastward extension of the magmatism of the Emeishan mantle plume. However, compared with the Emeishan high Ti/Y basalts, the Dahua dolerite shows obvious depletion of high field strength elements Nb, Ta, Zr and Hf, and exhibits relatively high ⁸⁷Sr/86Sr(t) values (0.710087~0.712849) and moderately lower εNd(t) values (-1.68~1.21)The data combined shows that the primary magmas of the Dahua dolerite have possibly originated from the material of Emeishan mantle plume, and the magma have subsequently mixed with the enriched lithospheric mantle material underlying the Yangtze block during its ascent. The Dahua dolerite is located in the middle of the Youjiang basin, far away from Ailaoshan-Majiang Suture Zone, and the Dahua dolerite and its surrounding areas do not reveal earlier or simultaneous subduction-related magmatic rocks. Therefore, the enriched lithospheric mantle involved in the Dahua dolerite may be formed by the modification of earlier tectono-thermal events.